Closure component

ABSTRACT

The invention relates to a closure component having a plurality of closure components ( 12 ) each disposed on a carrier part ( 10 ) by means of a footer ( 18 ) and each comprising a header ( 14 ) connected to the footer ( 18 ) by means of a shaft part ( 16 ), wherein the header ( 14 ) is jointedly connected to the shaft part ( 16 ) by means of a hinge part ( 20 ). Because the footer ( 18 ) forms a further hinge part ( 22 ), by meats of which the shaft part ( 16 ) is jointedly connected to the carrier part ( 10 ), improved adhesion to third components can be produced relative to the known solutions.

The invention relates to a closure component with a plurality of closure components which are spaced apart from one another and which are each located by means of a base part on a backing part and which each have a head part which is connected via a stem part to the base part, the head part being articulated to the stem part via an articulated part.

WO 2004/105536 A1 discloses a touch-and-close fastener part in which the free ends of the stem parts of the individual adhesion elements are provided with a plurality of individual fibers, and the diameter of the respective fibers has to be chosen to be very thin so that on the free end of each individual fiber only a very small contact surface is available, of the magnitude of 0.2 to 0.5 μm.

These orders of magnitude, which can also be in the nanometer range in preferred configurations, enable interaction with a corresponding body in the vicinity on which the touch-and-close fastener part is to be fixed by the so-called van der Waals forces which are classically considered as a subgroup of adhesion. The known touch-and-close fastener part has good connecting properties but is tied to a correspondingly cost-intensive production process.

This also applies to a touch-and-close fastener part according to the teaching of publication WO 01/49776 A2, which instructs one skilled in the art to use parts of the base structure of a gecko directly as biological material or to artificially simulate it, this adhesive structure consisting of a plurality of so-called spatula components which are each divided in the form of a bent cylindrical closure element on the free end into a plurality of individual filaments.

Conversely, for simplified production, DE 102 23 234 B4 proposed a method for surface modification of an object in the form of a closure component with the objective of increasing the adhesion capacity of the adhesion element. For this purpose, the free surface is exposed to structuring in order to form a plurality of projections which are each provided with a base part and a head part, the head part having an end surface pointing away from the surface and each projection being formed with a size such that all end surfaces have the same vertical height over the surface. This yields an adherent contact surface which is interrupted by respective distances between the end surfaces, the base parts of the projections being tilted relative to the surface normal of the surface.

With this known solution, it is possible to make available the execution of detachable adhesive connections for an expanded range of materials with increased adhesion capacity and the possibility of enabling the setting of predetermined adhesive forces or properties; however, based on the relatively rigid arrangement between the head part and backing part over the stem parts which may be tilted, there is room for improved solutions.

WO 2007/134685 A1 discloses a generic touch-and-close fastener part, the head part of each closure component consisting of a head disc whose diameter is chosen to be larger than the diameter at any point of the stem part which, made conical in shape, is articulated via an articulated part to the head disc. This results in that the head part certainly remains adhering to a body in the vicinity, even if the backing part should move axially in the plane-parallel direction to this body by a definable amount. As a result of the linking via the respective articulated part, located between the stem part and head part, the respective stem part can tilt within a definable framework in the oblique direction without this adversely affecting the linking of the head part relative to the body in the vicinity. Since moreoyer the head part with the head disc can have a very large diameter in the known solution, the possibility of adhesion to the indicated ambient body is improved accordingly.

Especially when vibrations occur during which the backing part executes short-stroke vibrations relative the body in the vicinity, the known touch-and-close fastener part has been found to be an effective connection solution.

Proceeding from this prior art, the object of the invention is to further improve the known solutions, in particular to supply improved adhesion and closure action for the respective touch-and-close fastener part with the simultaneous option of being able to produce these systems economically and with functional reliability. This object is achieved by a touch-and-close fastener part with the features of claim 1 in its entirety.

In that, according to the characterizing part of claim 1, the base part forms another articulated part by means of which the stem part is articulated relative to the backing part, compared to known solutions, improved adhesion relative to third components can be produced. Due to the second articulated part in the region of the base part, relative to the backing part a damping element is formed which relieves the first articulated part in the region of the head part, and this enables higher vibration and impact forces to be fed into the touch-and-close fastener part without it unintentionally detaching from the third component. Detachment of the head part in the manner of a peeling motion from the body in the vicinity as a third component only takes place when the head part is tilted via the respective articulated part by an angle of at least 20°, preferably of at least 40° relative to the vertical, and standing thereon in the vertical direction, the backing part is oriented with its alignment.

The good adhesive action formed in this way also fundamentally applies when a conventional option of hooking underneath is implemented for the closure component, for example, by a loop part of a corresponding touch-and-close fastener part engaging the closure component designed as a mushroom or hook part by hooking underneath. In these cases as well, it has been shown that as a result of the double articulation arrangement an improved closure action is achieved which, if necessary, however, can also be detached again mechanically or by hand in order in this way to form an adhesive closure which can be repeatedly opened and closed.

In one especially preferred embodiment of the touch-and-close fastener part according to the invention, it is provided that the respective stem part is made reinforced, in particular, is provided in cross section with a widening. This widening has at least in part the shape of a regular or irregular ellipsoid or is structured in the form of an elliptical paraboloid. As a result of the widened stem part, which extends between the two articulated parts on the head and base part, vibration stiffening of the entire system is achieved with increased support function for the indicated opposing articulation sites or articulated parts.

Other advantageous embodiments of the touch-and-close fastener part according to the invention are the subject matter of the other depending claims.

The touch-and-close fastener part according to the invention is detailed below using one exemplary embodiment as shown in the drawings. The single figure schematically shows, not to scale, a side view of the touch-and-close fastener part according to the invention with a total of three closure components located on a backing part.

The orders of magnitude addressed with the touch-and-close fastener part in the geometrical implementation should suffice and are designed such that an interaction with a corresponding part, whether in the form of another touch-and-close fastener part or in the form of the surface of a body in the vicinity on which the touch-and-close fastener part according to the invention is to be fixed, can preferably take place by way of so-called van der Waals forces. The so-called van der Waals forces which constitute a subgroup of adhesion are formed because the negatively charged electrons swirling around the positive core in an atom are briefly concentrated on one side. In this way, the atom on this side is temporarily negatively charged, while it is positively charged on the other side. This also affects adjacent atoms; in this case, the atoms along the top of the bearing surface of the head part, with the result that the bearing surface of the head part, depending on which charge it acquires, is attracted either by the positive or the negative atoms of the respective opposite ambient body surface.

The larger the arising contact surfaces are in total, the stronger the forces which occur so that it may prove to be effective to form head part bearing surfaces which are dimensioned to be large in order to obtain strong van der Waals forces. Although the van der Waals forces are considered to be among the weakest forces in nature, the effect is sufficient to achieve relatively high closure forces; in particular, considering that there can be several thousand closure elements on the extremely small space of the backing part. If the surface of the respective head part should be chemically modified for this purpose, genuine chemical bonding is also possible as the adhesion connection.

The touch-and-close fastener part shown in the figure, for purposes of this invention, can be obtained according to a micro-replication method, as described in DE 196 46 318 A1. The known method is used to produce a touch-and-close fastener part with a plurality of closure components 12 made in one piece with a backing part 10 in the form of stem parts 16 which have head parts 14 and which are connected in turn via base parts 18 to the backing part 10. Preferably, a thermoplastic in the plastic or liquid state is introduced into a gap between a pressure roll and a molding roll, the molding roll being provided with a screen, with cavities which are open to the inside and outside, and the two rolls are driven in the opposite direction of rotation for the production process so that the backing material is formed in the gap between the rolls with the formation of the backing part 10. Since for the touch-and-close fastener part according to the invention the stem parts 14 can be made crowned, the screen cross section is matched to the outer contour of the respective stem part 16, in particular, is designed as a regular or irregular ellipsoid of revolution; the desired shaping, as shown in the figure, would also be attainable by two paraboloids of revolution, which are facing one another with their free opening cross section. In this way, the indicated screen cross section therefore is to be matched to the shaping of the respective closure component 12.

Another possibility for obtaining the closure component system shown in the figure is shown in DE 100 65 819 C1. In this known method for producing the touch-and-close fastener parts, a backing material is provided in at least one partial region of its surface with touch-and-close fastener parts or adhesion elements which project out of the plane by a plastic material which forms the elements being applied to the backing element as backing part 10, the elements being made at least in one partial region without molding tools by the plastic material being deposited in successively released droplets by means of at least one application device. Although the application device delivers the plastic material with a droplet volume of only a few picoliters via its nozzle, a process sequence which is sufficiently fast thus can be implemented so that within an extremely short time frame a touch-and-close fastener part, as shown in the figure, can be obtained. With this method, individual adhesion elements in particular can also be produced which, in addition to the head part 14 and the stem part 16 as well as the base part 18, form two articulated parts 20, 22 which, viewed in the direction of looking at the figure, are shown at the extreme left as imaginary inscribed circles 24, 26 for better understanding and by way of explanation.

The stem part 16 in turn can be described in terms of its outside contour as part of a regular or, as shown in the figure, irregular ellipsoid of revolution 23, the centers 28 and 30 of the circles 24 and 26 respectively being located within the ellipsoid of revolution 23 or more or less on its imaginary edge boundary as shown for the center 30 of the circle 26. Instead of the illustrated ellipsoid of revolution 30, the outside contour of the stem part 16 can also be implemented via two paraboloids of revolution which run in opposite directions (not shown), whose free opening cross sections adjacently border one another. Overall, as a result of the crowned configuration of the stem part 16, a closure component structure, which is stiffened between the articulated parts 20, 22 and which extends between the two articulated parts 20, 22 of each closure component 12, is formed. As especially the increased radius of the circle 26 is intended to show, the articulated part 22 is made thicker in the region of the base part 18 than the overlying articulated part 20 in the direction of the head part 14, so that in the direction of the base part the damping action is improved and in this respect the stem part 16 over the articulated part 22 undergoes a smaller pivoting motion than in the region of the head part 14 with the upper articulated part 20. As the side view according to the figure shows, for the stem part 16, this yields a convexly running outside contour which extends between concavely running outside contour portions of the head part 14 and base part 18. Furthermore, the head part 14, proceeding from its articulation site 20 which can be assigned to it, tapers to the outside toward its peripheral edge 32 and there forms a narrow-lipped edge.

The respective closure component 12 consists preferably of a plastic material which is selected in particular from the group of acrylates such as polymethacrylates, polyethylenes, polypropylenes, polyoxymethylenes, polyvinylidene fluoride, polymethylpentene, poly(ethylene) chlorotrifluoroethylene, polyvinyl chloride, polyethylene oxide, polyethylene terephthalate, polybutylene terephthalate, nylon 6, nylon 6.6, and polybutene.

Fundamentally, plastics with long molecular chains and good orientation behavior as well as plastic materials with thixotropic behavior are highly suitable. Thixotropic behavior for purposes of the invention is intended to denote the reduction of structural strength during the shear loading phase and its more or less rapid but complete restoration during the subsequent resting phase. This breakdown/restoration cycle is a completely reversible process, and thixotropic behavior can be defined as a time-dependent behavior.

Furthermore, plastic materials have proven favorable in which the viscosity of 7,000 to 15,000 mPa, measured with a rotational viscosimeter, is sufficient; but preferably has a value of approximately 10,000 mPas at a shearing rate of 10 l/sec. For purposes of a self-cleaning surface, it has moreover proven favorable to use plastic material whose contact angle, as a result of its surface energy for wetting with water, has at least a value of greater than 60 degrees. Under certain circumstances, this surface energy can also be further changed by subsequent treatment methods.

With respect to the aforementioned requirements, polyvinyl siloxane has proven an especially interesting representative of suitable plastic materials, and this plastic can be used especially for the formation of head parts 14 and their free tops, and the entire closure component 12 including the backing part 10 can be composed of this polyvinyl siloxane plastic material.

The figure shows approximately 1,000 times enlarged the actual size ratios, and there can be 10,000 to 50,000, preferably 30,000, of these closure components 12 standing tightly next to one another per square centimeter on the homogeneous planiform or strip-shaped backing part 10. A uniform arrangement is preferred in which all closure components 12 in the form of adhesion elements have the same distance to one another; there is, however, also the possibility of making irregular arrangements here or those in pattern shape (round, star-shaped, ellipsoidal, etc.).

The head parts 14 which are disk-shaped in terms of the outside contour can also have other shapes, for example, can be made elliptical or polygonal in shape, the hexagonal shape having been found to be especially favorable, even with respect to the indicated screen shaping method, whereas for the stem parts 16, also with respect to the release from the shaping screen which is to be undertaken, a crowned structure is favorable.

The individual size ratios in the direction of looking at the figure are as follows for the closure component 12 at the extreme right:

Y1=30 to 55 μm

Y2=approx. 28 μm Y3=approx. 35 μm

Y4=40 to 65 μm Y5=30 to 65 μm

X1=approx. 2 μm X2=approx. 8 μm

X3=60 to 80 μm

While Y5 indicates the distance of two adjacent center axes of closure components 12, the distance is approximately 115 μm standing vertically on the plane of the drawing to the respective next closure component 12 which is located in the middle between two closure components 12 which lie in the plane of the figure, to the closure component 12 which lies comparably behind in the plane of the drawing. These size ratios are only exemplary and yield an especially favorable and well-functioning touch-and-close fastener part; however, other size ratios are also conceivable here.

Since the two articulated parts 20, 22 can be adjusted independently of one another, considerably more degrees of freedom than in the known single articulation solution in the region of the head part are possible. This in turn benefits improved linking even with strong stress on third components. 

1. A closure component with a plurality of closure components (12) which are spaced apart from one another and which are each located by means of a base part (18) on a backing part (10) and which each have a head part (14) which is connected via a stem part (16) to the base part (18), the head part (14) being articulated to the stem part (16) via an articulated part (20), characterized in that the base part (18) forms a further articulated part (22) by means of which the stem part (16) is articulated relative to the backing part (10).
 2. The touch-and-close fastener part according to claim 1, characterized in that the respective stem part (16) is made reinforced, in particular, is provided in cross section with a widening.
 3. The touch-and-close fastener part according to claim 2, characterized in that the widening has at least in part the shape of an ellipsoid (23) or an elliptical paraboloid.
 4. The touch-and-close fastener part according to claim 1, characterized in that the head part (14) on its free end side forms a contact surface which enables a redetachable adhesion to a body in the vicinity essentially by means of adhesion force.
 5. The touch-and-close fastener part according to claim 1; characterized in that a detachment of the head part (14) in the manner of a peeling motion from the body in the vicinity takes place when the head part (14) is tilted by means of the two articulated parts (20, 22) by an angle of at least 20°, preferably of at least 40°, relative to vertical, the backing part (10) being located running vertically thereto.
 6. The touch-and-close fastener part according to claim 1, characterized in that the outer periphery of the head part (14) is smaller than or equal to the outer periphery of the base part (18) at the site of its transition to the backing part (10).
 7. The touch-and-close fastener part according to claim 1, characterized in that the stem part (16) extends with a convexly running outside contour between concavely running outside contour portions of the head part (14) and base part (18).
 8. The touch-and-close fastener part according to claim 1, characterized in that the head part (14) proceeding from its articulated part (20) which can be assigned to it, tapers to the outside toward its peripheral edge (32), in particular discharges into a narrow-lipped edge.
 9. The touch-and-close fastener part according to claim 1, characterized in that at least parts of the head part (14) consist of polyvinyl siloxane. 